[Family and friends who smoke: influence on adolescents]

Smoking is the leading preventable cause of death. Most cigarette smokers take up the habit during adolescence. The purpose of this study was to assess the prevalence of cigarette smoking behavior among the students of a metropolitan high school as compared to those attending a non-metropolitan high school, examining age, sex and demographic and socioeconomic differences, as well as the influence of smoking models (family members and friends) on smoking behavior among adolescents.

Nine hundred seventy-eight students (544 males, 434 females; mean age 15.8 +/- 1.5 years) attending a high school in the city of Naples and 467 students (235 males, 232 females; mean age 16 +/- 1.5 years) from a high school of Capua, a small town 40 kilometers away from Naples, filled out an extensive questionnaire on smoking. The prevalence of smokers was 24.2% (males 21.8%, females 28.2%; p = 0.02) in Naples and 23.8% in Capua (males 29.8%, females 19.2%; p < 0.001) and was related to age (p < 0.001) both in Naples and in Capua. In Naples, smoking behavior among male students was associated with smoking by sibling (p = 0.00005), whereas an association with father (p = 0.0003), mother (p = 0.00005), parental (p = 0.0002) and sibling (p = 0.00002) smoking was observed among females. In Capua, an association was evident only between smoking in female students and sibling smoking habits (p = 0.02). In both Naples and Capua, smoking status of the students was related to smoking habits of best friends of the same sex, best friends of the opposite sex and friends. Multivariate analysis showed an independent relationship in Naples between adolescent smoking behavior and smoking status of siblings (p = 0.01), best friends of the same sex (p < 0.001) and best friends of the opposite sex (p < 0.001). In males, smoking behavior was associated with the smoking behavior of best friends of the same (p < 0.001) and of the opposite sex (p = 0.01), whereas in females, it was linked with the smoking behavior of siblings (p = 0.05), mother (p < 0.05) and best friends of the same sex (p < 0.001). In Capua, student smoking was related to smoking among friends (p < 0.001) and this held true for both males (p = 0.05) and females (p < 0.0001).

The prevalence of smoking habits among teenagers is similar in two distinct populations of high school students from a city and from a small town. Smoking showed a higher prevalence among females in the city and among males in the small town. It increases with age and is related to peer and family smoking models. This study has identified several variables associated with smoking status among adolescents. We thus feel that these findings may contribute to a better understanding of smoking behavior among teenagers and may have prevention implications.